110 research outputs found

    多媒體安全專題

    Get PDF

    多媒體安全專題

    Get PDF

    應用於跨平台之家庭數位版權協定與安全之研究

    Get PDF
    [[abstract]]目前商業上提供的平台皆屬於封閉型的系統,不過隨著智慧型手機的普及,消費者偏好在多種平台中使用相同的軟體,跨平台分享將是未來的趨勢主流,在不久的將來跨平台分享數位內容也將建立在家庭當中,引領全球進入嶄新的數位家庭時代。所以如何透過有效的方式來保護數位內容防止非法行為,並提高其安全性將是這個階段所需重視的課題。 之前相關研究中,所提出之協定皆只有改善封閉式檔案傳輸的問題,其主要是在確認數位版權的交易機制,不過並沒有做到安全上的考量。因此在我們所提出的CUHO協定,除數位版權分享的目的,並考慮到訊息傳遞安全的重要性,利用了密碼學上的挑戰回應並結合隨機雜湊鎖之理念,將每回合通訊之認證資訊加入隨機亂數以及時間戳記作運算,以達到不可追蹤性以及避免重送攻擊來提高安全性。[[sponsorship]]中國文化大學; 閩江學院海峽學院; 美國托萊多大學亞洲研究學院[[conferencetype]]國際[[conferencedate]]20130601~20130601[[booktype]]電子版[[iscallforpapers]]Y[[conferencelocation]]臺北市, 臺

    Image Watermarks Combining Direct Sequence

    No full text
    摘要 隨著網際網路、多媒體與電子商務的快速成長,資訊交換變得既快速又方便,也由於資訊的取得太容易了,對於個人私密性資料的保護與智慧財產權的保障就顯的非常的重要。 我們使用通訊系統中的展頻通訊原理來實現數位浮水印。將數位浮水印系統比擬成通訊系統,原始媒體資訊(影像)之頻率域為傳輸通道,而浮水印資料為傳輸訊號,可能遇到的攻擊或破壞則視為通道雜訊。 展頻通訊區分為直接序列展頻(Direct Sequence Spread Spectrum DSSS)與跳頻展頻(Frequency Hopping Spread Spectrum FHSS)二種,因此,我們針對這二種展頻技術而設計。並融合跳頻展頻與直序展頻的Combine-S Watermarking技術。Combine-S Watermarking可同時擁有跳頻展頻浮水印與直序展頻浮水印的優點,我們藉由調整Slow DSSS Watermarking與Slow FHSS Watermarking的比例抵抗不同的影像攻擊,藉此可以抵抗較多種的破壞,達到提高數位浮水印強韌度之目的。 最後我們得到Slow DSSS Watermarking與Slow FHSS Watermarking採用2:8的比例,可以抵抗大多數的攻擊,而且取出的浮水印仍有一定品質,因此2:8是一個可接受且優良的比例分配。Abstract With the rapid growth of Internet, information exchange is getting more and more convenient. As it is so easy to obtain others information in the networks, the issues of the privacy and copyright protection become more important to prevent unauthorized access. In the thesis, we developed two watermarking techniques using spread-spectrum technique. The watermarking technology can be viewed as a communication system. The watermark was the signal to be transmitted. The frequency domain of the original image was the transmission channel. The attacks were regarded as channel noise. There were two methods to implement the spread-spectrum system: direct- sequence spread- spectrum (DSSS) and frequency-hopping spread-spectrum (FHSS). Based on these two methods, we developed a method that combined FHSS Watermarking and DSSS Watermarking. We called the new method “combine-S Watermarking”. The experimental results proved that combine-S Watermarking had both the advantages of FHSS Watermarking and DSSS Watermarking. Therefore, combine-S Watermarking was more robust and can withstand many different attacks.第一章 緒論 1.1 關於數位浮水印 1.2 研究動機 第二章 數位浮水印之介紹 2.1 數位浮水印架構 2.2 數位浮水印特性 2.3 數位浮水印應用 2.3.1依應用區分數位浮水印 2.3.1.1以來源為導向的數位浮水印 2.3.1.2 .以目的為導向的數位浮水印 2.3.2依本身特性區分數位浮水印 2.3.2.1 以有意義圖為數位浮水印 2.3.2.2 具有統計特性的數位浮水印 2.3.3 依視覺品質來區分數位浮水印 第三章 空間域與頻域… 3.1 空間域與轉換領域 3.2 離散餘弦轉換 第四章 展頻通訊介紹 4.1 直接序列展頻 4.2 跳頻序列展頻 4.3 展頻數位浮水印研究方向 第五章 展頻技術之數位浮水印 5.1 直序展頻浮水印內容簡述 5.2 快速與慢速直序展頻浮水印 5.3 嵌入浮水印方法 5.4 取出浮水印方法 5.5 跳頻展頻數位浮水印 5.6 .快速跳頻展頻浮水印 5.7 慢速跳頻展頻浮水印 第六章 雙浮水印嵌入的展頻浮水印架構 6.1 融合慢速直序與慢速跳頻的數位浮水印 6.2 JPEG壓縮 6.2.1 混合比例抵抗JPEG攻擊 6.3 其他影像處理攻擊 第七章 結論 7.1 未來工

    應用影像邊界資訊與粒子群最佳化演算法之強韌數位浮水印技術

    No full text
    [[abstract]]對於數位內容的服務者和供應商,數位多媒體內容的保護,已經成為一個重要的議題。現今數位浮水印被定義為實現版權保護的重大技術。但是,實作一個具有強韌性之數位浮水印是有難度的。本論文提出一個強韌數位浮水印的演算法,我們結合了離散小波轉換和奇異值分解等技術。我們會利用影像中的邊界資訊再將數位浮水印嵌入於影像的邊緣特徵裡。此外,我們利用粒子群最佳化演算法求取嵌入與取出數位浮水印之最佳調整因子。實驗結果證實,本論文的方法具有高度的不可視性,而且對於多樣性的影像處理攻擊皆有很好的抵抗效果

    Digital Watermarking Based on Spread Spectrum Technique

    No full text
    電腦與通訊網路的進步,使得電子文件交換、電子商務、隨選視訊、數位圖書館等數位服務蔚為風尚。但是,由於數位化資料具有容易且精確地被複製的特性,所以需要有效的保護機制來防止竊取或篡改,數位浮水印(digital watermarking)就是產學界高度重視的技術之一。數位浮水印技術為近年來新興的技術,它能將資訊隱藏於多媒體資料中用來宣告所有權、著作權或認證。 在我們的研究上,我們是使用通訊系統中的展頻通訊原理來實現數位浮水印。本文將數位浮水印系統比擬成通訊系統,原始媒體資訊(影像)之頻率域為傳輸通道,而浮水印資料為傳輸訊號,可能遇到的攻擊或破壞則視為通道雜訊[1][23]。展頻通訊已區分為直接序列展頻(Direct Sequence Spread Spectrum DSSS)與跳頻展頻(Frequency Hopping Spread Spectrum FHSS)二種,因此,我們針對這二種展頻技術而設計出跳頻展頻浮水印(FHSS Watermarking)與直接序列展頻浮水印(DSSS Watermarking)。 JPEG壓縮是現今普遍使用的壓縮格式,因它有著高壓縮特性,以及壓縮後影像品質仍很高,所以普遍被大眾使用。在本論文中,我們針對JPEG壓縮方式提出其數位浮水印的嵌入構想,將浮水印嵌入於對JPEG量化有較強抵抗力的頻帶中,以達到提高抵抗JPEG壓縮之目的。由於JPEG是使用離散餘弦轉換將影像轉換至頻率域,為了配合其特性,所以我們的展頻數位浮水印在轉換領域部分也是基於離散餘弦轉換。 實驗結果顯示,我們所提出的跳頻展頻浮水印在維持影像品質的情形下,對於JPEG壓縮具有高度的強韌性,另外使用PhotoImpact 5影像處理套裝軟體來測試比較跳頻展頻浮水印與直序展頻浮水印對各種影像處理特效其抵抗破壞效能的優劣,我們發現跳頻展頻浮水印對幾何失真破壞比較有抵抗力,而直序展頻浮水印則是訊號處理破壞具有抵抗力。 本論文最後提出融合跳頻展頻與直序展頻的Combined SS Watermarking技術。Combined SS Watermarking可同時擁有跳頻展頻浮水印與直序展頻浮水印的優點,如此,Combined SS Watermarking技術便可以抵抗較多種的破壞,達到提高數位浮水印強韌度之目的。The advances of computers and communication networks make digital content service such as digital document exchange, E-commerce, video on demand, and digital library very popular. Since digital data can be easily reproduced without any loss, copyright protection becomes an imperative requirement to prevent piracy. Digital watermarking has been proposed as one of the techniques to prevent data piracy and plagiarism. Digital watermarking is a novel and emerging technology. It has developed very quickly for the past few years. A digital watermark is a set of information that is robustly and imperceptibly embedded in the data to be protected. Applications include copyright protection, and authentication. In the thesis, we developed two watermarking techniques using spread-spectrum technique. We interpreted the watermarking technology based on communication theory. The watermark was the signal to be transmitted. The frequency domain of the original image was the transmission channel. The attacks were regarded as channel noise. There were two methods to implement the spread-spectrum system: direct- sequence spread- spectrum (DSSS) and frequency-hopping spread-spectrum (FHSS). Based on these tow methods, we develop FHSS Watermarking and DSSS Watermarking. JPEG compression is the most widely used image because compression technique of its high compression ratio and reasonable image quality. Here, we develop the watermark embedding method especially for JPEG encoding process since block Discrete Cosine Transform (DCT) was used for JPEG. In our approach, a block DCT-based algorithm was used to embed the image watermarking. In order to survive the JPEG compression, the watermark must be embedded in the bands that can with stand the JPEG quantization. Experiments showed that FHSS Watermarking is more resistant to the attack of JPEG compression. The PhotoImpact 5 digital image processing software was used for other attacks. We found that FHSS Watermarking is more robust than DSSS Watermarking in geometric distortions. But in other signal processing modifications, DSSS Watermarking is more robust than FHSS Watermarking. Therefore, we developed a new method that combined with FHSS Watermarking and DSSS Watermarking, we call the new method “combined SS Watermarking”. The experimental results prove that combined SS Watermarking has both the advantages of FHSS Watermarking and DSSS Watermarking. Therefore, combined SS Watermarking is more robust and can with stand many different attacks.中文摘要……………………………………………………………...…I 英文摘要…………………………………………………………….….III 致謝 目錄 圖目錄 表目錄 第一章 緒論……………………………………………………….…….1 1.1 影像保密……………………………………………………..…1 1.2 何謂數位浮水印………………………………………………..2 第二章 數位浮水印的背景……………………………………………..4 2.1 系統設計與需求考量………………………………………….4 2.2 數位浮水印架構……………………………………………….5 2.3 數位浮水印特性……………………………………………….7 2.3.1數位浮水印之種類………………………………………..7 2.3.2浮水印影像……………………………………….……...9 2.4 影像品質定義………………………………………………..10 2.5 浮水印相似度衡量…………………………………………..11 2.6 浮水印嵌入之領域………………………………………..…14 2.7 嵌入浮水印於空間域……………………………………..…15 2.7.1 最低位元嵌入技術…………………………………...…15 2.7.2 拼湊法嵌入技術……………………………………...…17 2.8 嵌入浮水印於頻率域……………………………………...…18 2.9 展頻通訊介紹與展頻數位浮水印研究方向….……………..21 2.9.1 跳頻展頻………………………………………………...21 2.9.2 直接序列展頻…………………………………………...23 2.10 展頻數位浮水印研究方向………………………………….25 第三章 數位浮水印的破壞……………………………………………26 3.1 前言…………………………………………………...………26 3.2 JPEG壓縮影像特性簡介…………………………..…………26 3.2.1 JPEG壓縮所使用的技巧……………………..…………26 3.2.2 色相轉換……………………..………………………….27 3.2.3 取樣方式……………………..……………………..……28 3.2.4 離散餘弦轉換……………………………………….…...29 3.2.5量化……………………………………….……………….29 3.3 全域DCT與區塊DCT二者比較………………………..…..32 第四章 跳頻展頻技術之數位浮水印…………………………………34 4.1 跳頻展頻浮水印內容簡介………………………………..….34 4.2 快速跳頻展頻浮水印………………………………………...35 4.3 慢速跳頻展頻浮水印………………………………………...36 4.4 嵌入浮水印方法……………………………………………...38 4.4.1 產生跳頻碼與建立慢速跳頻表………………………....39 4.5 取出浮水一方法…………………………………………..….46 第五章 直接序列展頻技術之數位浮水印……………………………49 5.1 直序展頻浮水印內容簡述…………………………………..49 5.2 快速與慢速直序展頻浮水印………………………….….…50 5.3 嵌入浮水印方法………………………………………..…….51 5.3.1 建立慢速直序展頻表……………………………………52 5.4 人類視覺系統…………………………………….……….….54 5.5 取出浮水印方法……………………………………………...56 第六章 展頻數位浮水印強健度測試 6.1 跳頻與直序展頻浮水印壓縮強健度測試…………………...61 6.1.1 JPEG與JPEG 2000二者差異…………………………..69 6.2 影像處理與幾何破壞強韌度測試……………………….…..71 6.3 不使用原始影像取出浮水印…………………………….…102第七章 雙浮水印嵌入的展頻浮水印架構…………………………..103 7.1 融合慢速直序與慢速跳頻的復位浮水印………………….104 7.2 融合的展頻數位浮水印強健度測試……………………….107 第八章 浮水印嵌入於彩色影像技術………………………………..112 8.1 再談色相轉換……………………………………………….112 8.2 彩色原始影像嵌入浮水印………………………………….113 8.3 彩色影像數位浮水印壓縮強韌度測試………………...…..114 第九章 結論與未來工作……………………………………………..117 9.1 結論………………………………………………………….118 9.2 未來方向……………………………………………………..117 參考文獻………………………………………………………………11

    Complementary Digital Watermarking Technique Based on Wavelet Transformation

    No full text
    摘 要 影像數位浮水印是利用人眼無法察覺影像細微變化的弱點,將特殊的資訊直接嵌入原數位影像中;縱使影像資料經過加解密、壓縮、非惡意的或其它攻擊性的影像處理,所嵌入的資訊依然可偵測出來 在本論文中,提出一種利用小波轉換之互補式浮水印技術做為數位影像資料的保護,在高頻與低頻部份,分別以兩種不同方式,隱藏兩個浮水印,使其在遭受攻擊時,至少有一個浮水印能存活。同時在偵測浮水印過程中不需要原始影像來輔助,因而可節省記憶體儲存空間,且在模擬測試中也證明,可減少原始影像因加入浮水印所造成之失真。 我們針對photoshop 常做之一般影像處理,來驗證加入浮水印之影像經過JPEG壓縮、模糊化、銳利化、雜訊化、圖形裁剪處理後其浮水印偵測結果,結果顯示我們的方法在遭受一般影像攻擊時,大部分都至少有一個浮水印能存活。Abstract Digital image watermark is a technique which takes advantage of the inability of human's eyes to differentiate the subtle change of images. It is a special information embedded and hidden in the original image. Even if the image data is encrypted and decrypted, compressed, unintentional or any other kind of attack, the embedded digital image watermark can still be detected. In this thesis,we propose a complementary watermark technique which uses the skill of wavelet transformation to protect image data. Two complementary watermarks are hidden in the high and low frequencies respectively in the transformed frequency domain. Using this technique , there will be at least one watermark can survive under attack .Besides, in the process of retriever the watermark, the original image isn't needed. Thus,save a lot of memory. The simulation results show that distortion of the original image caused by the insertion of watermark can be minimized. we also examine the outcome of watermark detection under JPEG compression, blurring, sharpening, noise and cutting based on the average image processing skills of Photoshop. The results show that our method can survive from most of the attack.目 錄 第一章 緒論 1 1.1 簡介 1 1.2 動機與目的 4 1.3 論文架構 5 第二章 浮水印背景及小波函數 6 2.1 背景 6 2.1.1 數位浮水印 6 2.1.2 數位浮水印技術要求 7 2.2 小波函數及相關技術 8 2.2.1 小波函數 8 2.2.2 小波函數相關技術 8 2.2.2.1 Haar 8 2.2.2.2 JND 12 2.2.2.3 Quadtree 13 2.2.2.4 Cocktail Watermarking 14 第三章 互補式影像浮水印技術 18 3.1 概述 18 3.1.1 低頻數位浮水印 19 3.1.1.1 低頻數位浮水印加入演算法 19 3.1.1.2 低頻數位浮水印偵測演算法 22 3.1.2 高頻數位浮水印 22 3.1.2.1 高頻數位浮水印加入演算法 22 3.1.2.2 高頻數位浮水印偵測演算法 24 3.1.3 高頻加低頻數位浮水印 25 3.2 系統架構 26 第四章實驗步驟與結果分析實驗結果 28 4.1 軟體測試步驟 29 4.1.1 浮水印加入軟體測試 29 4.1.2 浮水印偵測軟體測試 31 4.2 實驗結果 34 4.2.1 失真壓縮 34 4.2.2 低通濾波模糊化 37 4.2.3 圖形裁剪 38 4.2.4 銳利化 43 4.2.5 雜訊化 44 4.2.6 反交錯式 48 4.2.7 紋理化、擴散光暈 49 4.2.8 雲彩化、鋸齒化 50 4.2.9 風動效果、多面體效果 51 4.2.10 馬賽克效果、去除斑點 52 第五章 結論與未來展望 55 5.1 結論 55 5.2 未來展望 55 參考文獻 5

    Image Watermarking Based on Block Mean Value Quantization

    No full text
    [[abstract]]基於區塊平均值量化的影像浮水印技術 摘要 自從網際網路風行以來,資訊流通快速,多媒體的著作財產權,逐漸受到嚴厲的考驗,版權保護將是未來首要的課題。本論文將以數位浮水印的技術來保護影像的版權,主要應用的技術如下所示: 1 混沌擾亂技術: 此為數位浮水印的前置演算法,為了資訊安全和不可視的要求,數位浮水印必須先行轉換成類似亂碼雜訊,再嵌入數位影像;然而取出必須利用交付版權所有者保留的密鑰,才能還原成真正的數位浮水印。所以即使有心和有能力的人,花費相當昂貴的時間和金錢後,得到的也只是無意義的資訊。 2 錯誤更正碼 此為數位浮水印的加強演算法,這裡使用了[7、4]漢明碼,數位浮水印嵌入前先行編碼和取出後再行解碼,本法可以簡單有效地加強數位浮水印的強韌性。 3 區塊平均值量化 此為數位浮水印的嵌入和取出處理演算法,本法利用JPEG對於平均值刻意保護的特性,以及noise的零平均值特性。所以在惡意的攻擊,都能有不錯的強韌性。而且本技術使用了空間領域和不需要原圖還原的方式,大量節省了儲存原圖的記憶空間。 為了證明本法的可行性,也利用了JPEG壓縮和noise干擾來進行攻擊。包括多種不同的JPEG壓縮倍率,和加法性雜訊、反轉性雜訊、乘法性雜訊三種不同主要的雜訊。最後自行開發人機介面視窗程式,方便使用者操作。而且和數位浮水印優異的上市產品進行各項比較,以證明本法的實用性和有效性。[[abstract]]Image Watermarking Based on Block Mean Value Quantization Student: Ren-Der Lin Advisor: Dr Chien-Cheng Tseng Department of Computer and Communication Engineering National Kaohsiung First University of Science and Technology Abstract The information interchange is very fast since internet is invented The illegal copy of the electronic multimedia become easier so the copyright protection is important research topic now This thesis presents a novel method for inserting binary watermark into image for protection The details of the method are given as follows: 1 Toral Automorphism It is a preprocessing algorithm of our digital watermarking scheme For the purposes of security and invisibility the binary watermark must be converted into noise like image and then insert into digital image The extracted watermark must have a private key of the copyright owner to restore the noise like image 2 Error Correcting Code This is an enhanced algorithm for the robustness of our watermarking scheme We use [7、4]Hamming code here 3 Block DC Value Quantization This is a embedding and extracting algorithm of our watermarking scheme this method uses two major image processing characteristics One is the DC Value invariant characteristic for JPEG compression the other is the zero mean characteristic of noise This algorithm performs in the space domain and watermark can be extracted without requiring the original image In order to show the effectiveness we also apply the compression of JPEG and interference of noise to attack the watermarking scheme In the JPEG attack we compare the performance for various JPEG compression ratios In the noise interference attack we use three major noises that are Gaussian-white noise salt & pepper noise and speckle noise Finally we develop the graphic user interference (GUI) window program for our scheme and compare it with the market product to demonstrate the effectiveness of our metho

    Embedding Security Keys in Images Using Digital Watermarks

    No full text
    由於電腦與通訊網路的進步,使得電子文件交換、電子商務、隨選視訊、數位圖書館等數位服務廣為流行。由於數位化資料很容易被複製,所以需要能防止竊取或篡改的保護機制。數位浮水印技術為近年來新興的技術,它能將資訊隱藏於多媒體資料中用來宣告所有權、著作權或認證。 在我們的研究上,我們是使用通訊系統中的展頻通訊原理來實現數位浮水印。本文將數位浮水印系統比擬成通訊系統,原始媒體資訊(影像)之頻率域為傳輸通道,而浮水印資料為傳輸訊號,可能遇到的攻擊或破壞則視為通道雜訊[4][9]。 JPEG壓縮是現今普遍使用的壓縮格式,因它有著高壓縮特性,以及壓縮後影像品質仍很高,所以普遍被大眾使用。由於慢速跳頻展頻浮水印技術主要是設計對抗JPEG壓縮。在多重傳送(Multicast)的環境下,我們想在同一張影像中放入二個不同的資訊,以提升影像的安全性,在本論文中,我們利用慢速跳頻展頻技術提出雙浮水印的嵌入構想,將浮水印嵌入於不同的頻帶中,實現將二個重要的資訊嵌入於同一張影像。 本論文最後提出利用二張不同的量化表,可讓二組key順利且無干擾的嵌入於同一張影像中,實現利用影像浮水印嵌入安全金鑰。The advances of computers and communication networks make digital content service such as digital document exchange, E-commerce, video on demand, and digital library very popular. Since digital data can be easily reproduced without any loss, copyright protection becomes an imperative requirement to prevent piracy. Digital watermarking has been proposed as one of the techniques to prevent data piracy and plagiarism. Digital watermarking is a novel and emerging technology. It has developed very quickly for the past few years. A digital watermark is a set of information that is robustly and imperceptibly embedded in the data to be protected. Applications include copyright protection and authentication. In the thesis, we developed two watermarking techniques using spread-spectrum technique. We interpreted the watermarking technology based on communication theory. The watermark was the signal to be transmitted. The frequency domain of the original image was the transmission channel. The attacks were regarded as channel noise. JPEG compression is the most widely used image compression technique because of its high compression ratio and reasonable image quality. In the multicast environment, we wanted to embed two different information to increase the security of images. Here, we developed an embedding method to embed two watermarks in the different bands. We used two different quantization tables to embed two keys in the same image, and realize embedding security keys in images using digital watermarks.中文摘要......................................................I 英文摘要....................................................III 致謝.........................................................V 目錄........................................................VI 圖目錄.......................................................X 表目錄.....................................................XIV 第一章 緒論...................................................1 1.1 影像保密..............................................1 1.2 何謂數位浮水印........................................1 第二章 數位浮水印的背景.......................................4 2.1 數位浮水印的評估標準..................................4 2.2 數位浮水印架構........................................5 2.3 數位浮水印特性........................................7 2.3.1數位浮水印之種類.....................................7 2.3.2浮水印影像...........................................8 2.4 影像品質定義.........................................10 2.5 浮水印相似度衡量.....................................11 2.6 浮水印嵌入之領域.....................................13 2.6.1 嵌入浮水印於空間域...............................14 2.6.2 嵌入浮水印於頻率域...............................14 2.7 展頻通訊介紹與展頻數位浮水印研究方向.................16 2.7.1 跳頻展頻.........................................17 2.7.2 直接序列展頻.....................................19 2.8 展頻數位浮水印研究方向...............................21 第三章 多路徑數量量化器......................................22 3.1 多路徑數量量化器介紹.................................22 3.2 多路徑數量量化器的公式化與表示法.....................23 3.3 多路徑數量量化器失真問題.............................25 3.4 理想狀況的條件.......................................26 3.5 在多路徑數量量化器性能下的失真率範圍.................28 3.6 標籤指定.............................................30 3.6.1 標籤指定介紹.....................................30 3.6.2 設計好的標籤指定條件.............................30 3.6.3 修正的巢狀標籤指定...............................31 3.6.4 修正的線性標籤指定...............................33 3.6.5 MN和ML標籤指定特性比較...........................35 第四章 跳頻展頻與多路徑數量量化器於數位浮水印上的應用........36 4.1 前言.................................................36 4.2 快速跳頻展頻浮水印...................................36 4.3 慢速跳頻展頻浮水印...................................38 4.4 嵌入浮水印方法.......................................39 4.4.1 產生跳頻碼與建立慢速跳頻表.......................41 4.5 取出浮水印方法.......................................47 4.6 加入MDSQ的浮水印.....................................49 4.7 MDSQ解碼器應用於浮水印的問題.........................53 4.7.1 問題產生原因.....................................53 4.7.2 問題解決方式.....................................53 4.8 模擬結果.............................................55 第五章 雙浮水印嵌入的展頻浮水印架構..........................60 5.1 研究動機.............................................60 5.2 雙浮水印嵌入.........................................60 5.3 雙浮水印取出.........................................63 5.4 模擬結果.............................................63 第六章 利用影像浮水印嵌入安全金錀............................66 6.1 研究方向.............................................66 6.2 重新修改量化表.......................................67 6.3 模擬結果.............................................70 第七章 結論與未來工作........................................76 7.1 結論.................................................76 7.2 未來方向.............................................77 參考文獻.....................................................7

    A DATA HIDING SCHEME BASED ON VQ AND SOC

    No full text
    [[abstract]]近年來,由於電腦與網路的通訊技術快速的發展,人們也注意到該如果保護通訊責料的安全。因此,資訊責藏的技術開始被提出與研究。隨著責訊資藏技術的發展,責訊責藏主要被分為二大領域:數位浮水印和隱藏學。數位浮水印是用來保護數位影像的著作權或是顯示擁有人。數位浮水印著重的是將浮水印藏入數位影像復,即使這些數位影像經過了一些常用的數位影像處理,還是能找出數位影像中的浮水影。隱藏學跟數位浮水印不同的是,隱藏學的目標在於將密秘責訊藏入影像中,讓欄截者發現不出異常,以達到密秘通訊的目的。隱藏學的主要議題是如何隱藏入更多的責訊以及如何保持藏入責訊復的偽圖的影像品質。隱藏學根據資訊隱藏方法的不同,主要分為空問域的資訊隱藏法和頻率域的資訊隱藏法。 在本篇論文中,我們提出了一個新的灰階影像的隱藏法基於Vector Quantization compression ( VQ )和Search 一Order codin 劇SOq 。我們的方法利用4 個編碼簿以及VQ 與SOc 的編碼排列組合,可以在一對VQ 區塊中藏入6 位元的資訊,隱藏的資訊量是Yu 等人方法的兩倍,而且偽圖的影像品質也可以保持跟Yu 等人方法的影像品質一樣
    corecore